Some Myths about Nutrition & Physical Activity

Are you overwhelmed by daily decisions about what to eat, how much to eat, when to eat, and how much physical activity you need to be healthy? If so, don’t be discouraged because you’re not alone. With so many choices and decisions, it can be hard to know what to do and which information you can trust.

This information may help you make changes in your daily eating and physical activity habits so that you improve your well-being and reach or maintain a healthy weight.

Food Myths

Myth: To lose weight, you have to give up all your favorite foods.

Fact: You don’t have to give up all your favorite foods when you’re trying to lose weight. Small amounts of your favorite high-calorie foods may be part of your weight-loss plan. Just remember to keep track of the total calories you take in. To lose weight, you must burn more calories than you take in through food and beverages.

TIP: Limiting foods that are high in calories may help you lose weight. The Dietary Guidelines for Americans 2015-2020 have estimated daily calorie needs based on a person’s age, sex, and physical activity level. The U.S. Department of Agriculture (USDA) SuperTracker tool may help you track the foods and beverages you eat and drink, as well as the physical activity you do.

Myth: Grain products such as bread, pasta, and rice are fattening. You should avoid them when trying to lose weight.

Substituting whole grains for refined-grain products is healthier and may help you feel fuller.

Fact: Grains themselves aren’t necessarily fattening—or unhealthy–although substituting whole grains for refined-grain products is healthier and may help you feel fuller. The Dietary Guidelines for Americans 2015-2020 recommend consuming grains as part of a healthy eating plan. At least half of the grains you eat should be whole grains. Examples of whole grains include brown rice and whole-wheat bread, cereal, and pasta. Whole grains provide iron, fiber, and other important nutrients.

TIP: Try to replace refined or white bread with whole-wheat bread and refined pasta with whole-wheat pasta. Or add whole grains to mixed dishes, such as brown instead of white rice to stir fry. Check out ChooseMyPlate for more tips to help you add whole grains to your eating plan.

Myth: Choosing foods that are gluten-free will help you eat healthier.

Fact: Gluten-free foods are not healthier if you don’t have celiac disease or are not sensitive to gluten. Gluten is a protein found in wheat, barley, and rye grains. A health care professional is likely to prescribe a gluten-free eating plan to treat people who have celiac disease or are sensitive to gluten. If you don’t have these health problems but avoid gluten anyway, you may not get the vitamins, fiber, and minerals you need. A gluten-free diet is not a weight-loss diet and is not intended to help you lose weight.

TIP: Before you decide to avoid a whole food group, talk with your health care professional if you believe you have problems after you consume foods or drinks with wheat, barley, or rye.

Myth: You should avoid all fats if you’re trying to be healthy or lose weight.

Fact: You do not have to avoid all fats if you’re trying to improve your health or lose weight. Fat provides essential nutrients and should be an important part of a healthy eating plan. But because fats have more calories per gram than protein or carbohydrates, or “carbs,” you need to limit fats to avoid extra calories. If you are trying to lose weight, consider eating small amounts of food with healthy fats, such as avocados, olives, or nuts. You also could replace whole-fat cheese or milk with lower-fat versions. Read about food portions and how much food is enough for you.

TIP: The Dietary Guidelines for Americans 2015-2020 recommend consuming less than 10 percent of your daily calories from saturated fats. Try cutting back on solid-fat foods. Use olive oil instead of butter in cooking.

Myth: Dairy products are fattening and unhealthy.

Fact: Dairy products are an important food group because they have protein your body needs to build muscles and help organs work well, and calcium to strengthen bones. Most dairy products, such as milk and some yogurts, have added vitamin D to help your body use calcium, since many Americans don’t get enough of these nutrients. Dairy products made from fat-free or low-fat milk have fewer calories than dairy products made from whole milk. Learn more about the dairy group.

TIP: Adults should have 3 servings a day of fat-free or low-fat dairy products, including milk or milk products such as yogurt and cheese, or fortified soy beverages, as part of a healthy eating plan. If you can’t digest lactose, the sugar found in dairy products, choose fortified soy products, lactose-free or low-lactose dairy products, or other foods and beverages with calcium and vitamin D:

Calcium—soy-based beverages or tofu made with calcium sulfate, canned salmon, or dark leafy greens such as collards or kale

vitamin D—cereals or soy-based beverages

Myth: “Going vegetarian” will help you lose weight and be healthier.

Some research shows that a healthy vegetarian eating plan may be linked to lower obesity levels.

Fact: Some research shows that a healthy vegetarian eating plan, or one made up of foods that come mostly from plants, may be linked to lower levels of obesity, lower blood pressure, and a reduced risk of heart disease. But going vegetarian will only lead to weight loss if you reduce the total number of calories you take in. Some vegetarians may make food choices that could lead to weight gain, such as eating a lot of food high in sugar, fats, and calories.

Not all vegetarians are the same.
The types of vegetarian diets eaten in the United States can vary widely. For example, vegans do not consume any animal products, including milk and eggs. Lacto-ovo vegetarians eat milk and eggs along with plant foods. Some people have eating patterns that are mainly vegetarian but may include small amounts of meat, poultry, or seafood. Speak with a registered dietitian or health care professional if you are concerned about whether your eating plan is providing all of the nutrients you need.

Physical Activity Myths

Myth: Physical activity only counts if you do it for long periods of time.

Fact: You don’t need to be active for long periods to get the amount of regular physical activity recommended in the Physical Activity Guidelines, which is at least 150 minutes, or 2 hours and 30 minutes, of moderate-intensity physical activity each week. An example of moderate-intensity activity is brisk walking. You can spread these sessions out over the week and even do short, 10-minute spurts of activity 3 times a day on 5 or more days a week.

TIP: Find ways to build short bursts of physical activity into your day. While at work, take a 10-minute walking break or have a “walking,” rather than a “sitting” meeting, if work and schedule permit. Use stairs instead of an elevator or escalator. Get off the bus one stop early. Meet a friend for a walk, instead of a meal.

Myth: Lifting weights is not a good way to improve your health or lose weight because it will make you “bulk up.”

Do muscle-strengthening activities at least twice a week.

Fact: Lifting weights or doing other activities 2 or 3 days a week that may help you build strong muscles, such as push-ups and some types of yoga, will not bulk you up. Only intense strength training, along with certain genes, can build large muscles. Like other kinds of physical activity, muscle-strengthening activities will help improve your health and also may help you control your weight by increasing the amount of energy-burning muscle.

TIP: Using large rubber bands, or resistance bands, or doing sit-ups or household or yard chores that make you lift or dig, may help you build strong muscles.

Don’t just sit there!
Americans spend a lot of time sitting: at desks, in cars, and in front of computers, TVs, and other electronic gadgets. Break up your sitting time by getting up and moving around, even if it’s for only 10 minutes at a time. Those minutes will add up over days and weeks.

Clinical Trials

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and other components of the National Institutes of Health (NIH) conduct and support research into many diseases and conditions.

What are clinical trials, and are they right for you?

Clinical trials are part of clinical research and at the heart of all medical advances. Clinical trials look at new ways to prevent, detect, or treat disease. Researchers also use clinical trials to look at other aspects of care, such as improving the quality of life for people with chronic illnesses. Find out if clinical trials are right for you.

What clinical trials are open?

Alternate Versions

This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases
(NIDDK), part of the National Institutes of Health. The NIDDK translates and disseminates research findings
through its clearinghouses and education programs to increase knowledge and understanding about health and
disease among patients, health professionals, and the public. Content produced by the NIDDK is carefully
reviewed by NIDDK scientists and other experts.

The NIDDK would like to thank:
Dr. Catherine Loria, Senior Scientific Advisor, Division of Cardiovascular Sciences, National Heart, Lung and Blood Institute; Dr. Richard P. Troiano, CAPT, U.S. Public Health Service, U.S. Department of Health and Human Services

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